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    <title>Document</title>
    <style>
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            width: 200px;
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        p{
            display: inline;
        }
        #box1{
            display: none;
        }
        
    </style>
</head>
<body>
    <div id="box">
        <input type="checkbox" name="" id="">
        <p>两周内自动登录</p>
        <div id="box1">
            测试
        </div>
    </div>
</body>
</html>

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    oDiv.onmouseover = function() {
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